When triggered actions occur

Triggered actions can occur before or after trigger events. Specifically, a triggered action can occur:

• Before a trigger event acts on a row.

  Example: A DELETE operation is scheduled to delete ten rows of Table X. If any of these rows contains a value under 5 in Column Y, the value must be copied to another table before the row is deleted. You can code a triggered action to look for a value under 5 in Column Y and, if the value is there, to copy it into the other table. The action will then be invoked against each row before the row is deleted.

  In the Create Trigger notebook, you specify when this action occurs by selecting the Before radio button under Time to trigger action on the Trigger page. When you do so, the Row radio button under For each on the Triggered Action page is automatically selected for you.

• After a trigger event acts on a row.

  Example: The number of rows in Table A is denoted by a value in Table B. You can code a triggered action to increase this value by 1 whenever an INSERT operation adds a row to Table A.

  In the Create Trigger notebook, you specify when this action occurs by selecting:

  • The After radio button under Time to trigger action on the Trigger page

  • The Row radio button under For each on the Triggered Action page

• After a trigger event acts on all the rows that the event applies to.

  Example: An UPDATE operation is scheduled to update ten rows in Table X. After the updates are made, a report summarizing them needs to be created. You can code a triggered action to create this report.

  In the Create Trigger notebook, you specify when this action occurs by selecting:

  • The After radio button under Time to trigger action on the Trigger page

  • The Statement radio button under For each on the Triggered Action page

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